Concrete-tamping machine and method



1,702,798 E. J. SCHUH concnnw TAMPING MACHINE AND METHOD Filed Nov. 7 1927 s Sheets-Sheet l INVENTOR ATTORNEY Feb. 19, 1929.

Feb. 19, 1929.

E. J. SCHUH CONCRETE TAMPiNG MACHINE AND METHOD Filed Nov. 7, 1927 3 Sheets-Sheet 2 7 I l I l mmw n H cflww m 2 M W W i m 9 m M r 7/ x/ .\+fl m M 7/ w J 1% fl i i m a Q Feb. 19, 1929. v

J. scHuH CONCRETE 'iAMPING MACHINE AND METHOD Filed Nov. 7, 1927 3 Sheets-Sheet INVENTOR MMJZS' M 1 Ml ATTORNEY has reached the mold.

Patented Feb. 19, 1929."; 1 J

EDWARD J. serum, or sroxnnn, wAsnmoToir,

C NCRETE-"minute MACHINE AND METHOD."

Application filed-November 7, 1927 Serial No. 231,702.

The object of this invention is to providean improved method and mechanism fortamping concrete and similar compositions andthe invention is especially adapted for the manufacture of bricks, blocks-and like useful arti-' cles made therefrom, j a

One'fea-tureof the inventi'onconsists in imparting to :a given area of concrete a succession of tamping impacts in rapid following relation, one upon the other, so that theme-1 terial acted upon will not only be more dense but also more uniform. t

In this connectiom wh-ere a mold isem ployed, it is a feature of the invention to use a tamper of reduced cross section with respect to the interior of the mold so that under the action of quick successive tamping,,the material will be not only reduced to a maximum and uniform density immediately under f the tamper, but thelatter will, drive-the excess material late-rally so-that various forms of interior configuration of molds canbe u-ni-, formly filled.

In a more specific phase of my invention, I

employ a tamper with a means coacting therewith to obtain in one single ,strokeof the tamper, a plurality of ,tampi-ng impacts, and preferably, one impact is obtained through one character of agency and other-impacts through another character of'agency.

My invention involves an actuatingmeans that operates through a fixed and predeten' mined cycle, in combination with a floating cross head and a floating tamper andgravity means; 7

- Other features and objects of the invention will be more fully described in connection with the accompanying drawings and will be more particularly point-edout in and by the appended claims. In the drawings; Fig. 1, is a view in elevation ,ofimproved tamping mechanism, a

Fig. 2,,is an edge elevation thereof with the parts in an elevated or starting position.

Fig. 3, is a similar view showing the posif' tion of the parts-1n that lnt al movement just prior to tension of the springs.

' Fig. 4, is. a similar view showing afu'rther movement after the springs ha'vebeen tensioned.

Fig.1 o, is a final position after the tamper Fig. 6.. is a vertical sectional;'viewon line 6-6 of Fig. 1, looking tothe left, showingz the such "details are within the skill knowledge of this art.

v may be of 'a' single width throughout its height from the top 14 to the bottom 15. *The parts in a position similar to that shown in Fig 3.

. Fig, 7, is a view similar to Fig. 6, showing the arts in a position similar to Fig. 5 s

Likecharacters of reference designatesimia lar parts throughout the different figures of the drawings. 7 1 4 I As -shown, the device of my invention includes a frame having similar side members '1, connected at their upper ends at 2 and having a suitable supporting base 3. The frame isshown provided with any suitable character ofmoldsupporting shelf 4 upon which a mold 5, isoshown. LI have notdetailed any means for centering the mold in a predetermined position on the shelf as my invention does not pertain to such features and further,

and common be made to my Zimproved actuating means which operates through a fixed'and predetermined cycle of I Reference will first movement.

A power shaft 6, is journalled in suitable bearings 7, in frame members 1, and on .one end; ofsaid shaft is a crank 8,-connected with a link 9'. On-the remaining end issa crank 10,

connected with a link 11, the cranklO haying acmnkhandle 12, suitable for the appliestion of manualpower although mechanical power may be of course applied The links 9 and 11 are connected at their upper ends with what I will call actuating shoes, both of which are alike in structure and functionand only one of 'wl iich need be described in detail, 0' the same reference letters beingapplied to.

Thetfram'e members lare each provided with'a slide-way in the form of a slot 13 which shoe comprises a shank 16, extending through V the slot and a relatively short guide 17, on the inside of member 1, and a relatively long guide 18, onthcl outside of member 1, whereby the shoe is held to a fixed path of recipro- I cation. The elongationof the outer guide 18-, v ispartly to afford adequate bearingsurfaoe and partly to form an actuating end and 1 abutment for a cross head which will be presently described. Projecting from the extrarior of the shoe is a link boss 19, to-whichxthe "respectiveflinks 9 and 10 are pivoted in order.

to impart reciprocating movement" to. the

shoes as i a result of rotation of the cranko'rv no power shaft 6. Said boss 19, has a reduced shank 20 which may be provided with a nut 21, for an operative connection with the cross head next to be described.

I will next describe the cross head that is operated by the heretofore described actuating means.

My cross head is designated at 21 and may be, as shown, of uniform cross section and of a length sutlicient to span the frame members 1 and project therethrough with the ends 22 extending beyond said members 1, as shown. Said cross head may be provided with inside flanges 23, adapted to slide along the inside faces of frame members 1, to hold the cross head against lengthwise movement therein and in a horizontal position. The ends 22, are shown provided with studs 24, having nuts 25. Said cross head is operatively connected with the actuating means, preferably yieldingly, by springs 26, the same being tension springs, having their ends 27 and 28, respectively, connected with studs 20 and 24, as shown. The cross head 21, is ac tually'floatingly mounted. in the frame, in the sense that it 1 artakcs of movement of a variable nature with respect to the movement of the actuating means to which it is operatively connected. When in the starting position shown in Fig. 1, the cr ss head rests upon the abutments 29, which are formed by the upper ends of guides 18. In this position, the parts are so arranged and proportioned that the springs 26, are not under tension but they perform the useful function of insuring descent of the cross head with the actuating means in the event that friction or other imperfections of the parts tended to retard gravity descent of the cross head. Thus while the springs 26 are not under any tension, preferably, in the 1, position, they do form a connecting means functioning posi- V tively. However, where the machine is in goodworking order and properly made, the importance of this function of the springs 26, would be of a secondary nature.

Reference will next be made to my improved tamper and the manner in which it is mechanically associated with. the cross head. My improved tamper consists, as shown, of a relatively heavy'body portion 30, which will preferably be made of metal and will be of suflicient weightto readily seek by gravity any position which it is free to assume. The cross section of the tamper body 30, will be designed and proportioned in accordance with the size mold employed. In the drawings, I have shown the tamper to be of a cross section less than the interior of the mold 5, toafford clearance all around of a greater extent than a mere working clearance. Said tamper body 30, is reduced to form a shank 31, the reduction forming what I will term an impact shoulder 02, for a useful purpose that wlll presently be described. 'The shank 31, is provided with a slot 33, which is slidably associated with a centrally reduced portion 34, of the cross head 21, as clearly shown. This slot 33, having alength greater than the major cross section of the cross head, affords t is tamper some relative movement independent of the cross head whereby it Wlll be seen that the tamper is fioatingly connected is associated with the tamper by being slotted as shown at 36, for slidable projection ther through of the shank 81. Functionally, the association of the weight and tamperrelates more particularly to the factthat the weight 35 coacts with the impact shouider62, of the tamper. The weight 35, is fioatinglyassociated with the tamper and means is'pro vided for supporting the weight and re'stricting its action on the tamper to a predetermined period of operation, which meansl will next describe. 7 i

Bars 37, are rockably mounted their opposite ends in frame members 1 and are shown supported on their lower edges 38, in suitable openings 39, in said frame. The shape of the openings is clearly shown in Fig. 2, and the walls of theopenings serve to limit rocking movement of .the bars ironi wdght supporting'to weight releasin p0 ,ns, andv vice Versa. Meanss ch as posed between the or. ends of tne bars id suitable abutmentstl, normally urge said bars 37, into a weight snpporti position. The upper edges 42, of said bars serve for direct engagement with the end portions of weight 35, as will be clearly seen in Fig; 6. I will nextrevert back to the snoes, and to Fig. 2, wherein it will be seen that I have provided the outside guides 18, with cams As the shoes descend, these cams e3, wedge the upper edges of the bars 87, outwardly, as will be seen in Fig. l, to release the weig; it 5. On ascent of the shoes, the cams 43, will readily pass between the bars 8?,by forcing them apart, the spring returningthe bars to again restore them into a position to support the weight. r

I will next describe the operat-ion'of the device and the method of my invention;

In the starting position shown in F 1, V

the links 9 and 11, support the shoes in an uppermost posit-ion and the shoe abntments 29, support the cross head 21, in anuppermost position. The weight of the tamper will normally cause the latter to assume theposi 40, intertion shown b gravity, but in anv event the weight 35 would limit upwardmovement of the tamper beyond the 1, position. The weight 35, is supported in the Fig. 1, position, by the bars 87. As shown in Fig. 6, only a small amount of concrete is disposed in the mold 5, and concrete will bev gradually fed into the mold to. an increasingdepth until the mold is slightly overfilled. I have not 1 shown a feeding means as the latter is not a partof this invention; However, in my Patent No. 1,581,814, issued April 20, 1926, on titled Machine for making concrete products, there is shown and described a feeding means that would be advantageously adapted for use in connection with my present tamping device. In this patent, the tamper is smallerin cross section than the interior-of the mold is temporarily arrested and as the shoes further descend, the springs 26 will be ten,-

sioned, as shown in Fig.-4. In this latter position, the shoes havedescended sufiiciently further totension the springs 26 and the cams 43, arejust about in ajposition to actuate the bars 37. After the cams 43, have actuated the bars 37, the weight 35, will be released and just as soon as weight- 35 is released, then the springs instantly contract. thereby imparting averysudden and powerful downward impulse to the cross head 21.-: The cross head 21, will follow the weight 35 and remain in engagement therewith because the rate of speed of descent of the cross head'21, under the action ofthe contracting springs'26,"will besuflicient to cause the cross head to main tain the same relation with respect to the weight 35 for a limited extent of travel. Of course, the tamper will also descend with the cross headand weight.

At this lpoint l desireto' draw attention to" a' very important feature which can readilybe seen by reference to Fjg. 6. It" will be noted that the lost motion betweenthe bottom of the cross head 21 and the bottomof slot 33,

ismany timesless than the distance between the bottom of weight 35 and the impact" shoulder 32. Now as the parts descend, the

tamper 30 will first strike the concrete, which will be the initial impact ofthe downward stroke of the tampon-This will arrest the tamper, or rather stop "further downward movement thereof. The descendingcross head will next strike the bottom of slot. 33,"an d' this will constitute the second impact-of the single downward stroke. 7 Immediately after the cross'head has struck thetamper, the" weight 35 will strike shoulder 32, and this willconstitute the third impact of the one and single downward stroke of the tamper." I

Now it will be clear that even though the initial impulse of the cross head is imparted tot-he weight 35,;before it is imparted to the tamper, and even if the weight 35 is actually above the tamper, still, because of the slight lost motion betweenthe bottom of the cross head andthe bottom of slot 33, as compared to the far greater distance between'the bottom of weight 35 and shoulder 32, it will be clear that the cross head will impact onto said tamper before the weight does.

Fig. 4, illustratesthe exterior parts in the position where the bars 37 are ust about to be actuated to release the weight 35, and at such point, the cranks Sand 10 are nearly to the deadcenter point of the first half of revolu-- ti'on of the shaft 6; When the tamper strikes the concrete, irrespective of the extent of fill of the mold, the cross head 21 will be; free from engagement with the abutment-s 29, so

that the springs 26 will be free to exercise their full strength in imparting a downward thrust to the'cross head 21. It will be clear that if the abut'ments 29, arrested the cross head 21, before the tamper 30i'st-ruck the concrete, that such interference would rob the tamper of the full force of its tamping blow. Hence, by reference to Fig. 5, it will beseen that there is a clearance between the abutments 29 andthe cross head 21 and that the springs 26 are still tensioned by reason of the fact that-the cranks 8 and 10 have' reacheda lower dead center position, and the springs have yielded in order that the cranks could 'negotiate'the lower turn. A corresponding 'position'showing the interior parts, is illustratedin Fig. 7; v

Now'as the shaft 6, continues in a clockwise direction,viewing Fig.7, the springs 26', will first be slackened and then the abutments 29 will engage the-cross head 21 and lift the latter. This lifting of cross head 21 will take up the lost motion between the top of'c-ross'head-21 and the top-0f slot 33, as shown in-Fig. 7 and the tamper and weight- ,Willbe elevated to'theinitial'position, as will now clear from the foregoing position.

43;pass,and will immediately thereafterbe returned by springs 39, to the 2, position. L It will now be clear that because the springs 26 are under tQDSlOllWllBIl thetamper The bars 37, will first be spread to let the cams i strikes the concrete, initially, that the tamper cannot rebound, but will be held tof its position of impact with-the concrete-throughout the period during whichtl'ie cross head 21 and weight 35, successively strike the tamper.

Concrete mudis very sluggish material to feed, especially to feed rapidly, and further,

itrequires thorough tamping. Nowv it has always been a problem to effect-ively tamp I concrete as rapidlyas it could be fed,'and I have solved the problem, not by increasing the actual rate of speed of the tamper, which would be objectionable, but by the' novel method and mechanism whereby in one single downward stroke of the tamper, three distinct impacts are made on the same area of material, namely, the concrete.

It will be clear that the springs 26, initially impart the downward thrust to the weight 35, but after the cross head strikes the tamper, then, the remaining fall of the weight into engagement with shoulder 32, is by gravity. Of course this gravity movement of the weight is very greatly accelerated by the mo mentum initially imparted to the weight by the springs 26.

By reason of the difference in the lost motion conneetionbetween the cross head and the tamper, on the one hand, and the difference in spaced relation of the weight 85 with respect to the shoulder 32, on the other hand, I can carry out the device of my invention with the operation herein disclosed, irrespec 'tive of the difference in weight as between the tamper 30, and weight 85.

It will be understood that while I have used the term concrete throughout the specification and claims, that this term is used generically to cover like or similar com positions, such for instance as magnesite, saw-dust and cinders, where a suitable binder is inherently or additionally present.

It is believed that the invention will be clearly understood from the foregoing description, and while I haveherein shown one specific form of my invention, I do not wish to be limited thereto except for such limitations as the claims I claim: 1. In a concrete tamping machine,-a frame having a shelf adapted to support a mold,

may import.

a horizontally disposed cross head floatingly slidable vertically in said frame toward and away from said mold, a vertically disposed tamper havi a reduced shank providing an impact shoulder and said shank having lostmotion slotted connection with said cross head, a tamper impact weight shdable on said shank between saidshoulder and cross head, retaining bars rockingly mounted in said frame and normally supporting said weight against downward movement and act- ..ing through said weight to limit downward movement of said cross head and tamper, power actuated shoes slidable vertically in said frame and having upper cross head actuating portions for positively elevating said err head tamper and weight, springs conneeting said shoes with said cross head for imparting downward movement to the latter. and cams on said shoes for rocking said bars to release said weight after initial movementof said shoes h as tensioned said springs,

' whereby said tamper will first strike the concrete and said cross head will next strike said tamper and finally said weight Wlll strike said tamper.

2. In a concrete tamping machine, a frame having a shelf for supporting a mold, across head floatingly slidable in said frame, a tamper having an impact shoulder andv hav ing lost motion connection with said cross head, a tamper impact weight for engagement with saidfshoulder, retaining members normally retaining said weight against downward movement and acting through said weight to arrest downward movement of said cross head, power actuated shoes slidable in said frame and positively engaging said cross head toelevate the latter, and springs connecting said shoes withsaid cross head to impart quick downward movement to the latter, and cams on said shoes for actuatingsaid members to rel-eise said weight after initial movement of said shoes has tensioned said springs, thereby impelling'movement of said tamper against the concrete and subse quent movement of said cross head and weight against said tamper,- respectively.

3. In a concrete tamping machine, a mold, a tamper therefor, spring means impelling saidtamper, and gravity means for impact- 1 ing on said tamper afterv the latter has en gaged the mold contents. w

a. In a concrete tamping machine, a mold,

a tamper therefor, means impelling said tamper, and means impacting on said tamper after thelatter hasengagedthe mold contents. y r

5. In a concrete tamping machine, a mold, a tamper therefor, and mechanism imparting successive tamping concussions to said tamper in one tamping stroke of the latter;

6. In a concrete camping machine, a mold,

a tamper. therefor, a normally supported '7 means to release said weight and tamper to first engage said tamper with the mold contents and subsequently permit said weight to impact on said tamper.

8. In a concrete tamping mechanism, a frame supporting a mold, a floatingcross head slidable in said frame, a tamper having lost motion connectionwith said cross head, actuating shoes having a fixed cycle of move-' ment in said frame and provided with abutments for elevating said cross head, and springs connected with said shoes and cross head for causing initial engagement of said tamperwith the mold contents and subsequent. engagement of said tamper by said cross head. P

9. In a concrete tampingi mechanism, a frame, a mold thereon, a floating cross head slidable in said frame, a tamper having lost motion connection with said'cross head, for tamping concrete in said mold of increasing -depths,and means yieldingly connected with said cross head for imparting tamping move-r ment to said tamper.

10. In a concrete tamping machine, a

frame, a mold thereon, a cross head slidable in said frame, a tamper having lost motion connection with said cross head, means for resisting tamping movement of said tamper, and mechanism yieldingly connected with said cross head for actuating said tamper and releasing said means.

11. The herein-described method of tamping concrete, which consists, in imparting an impact thereon and in subsequently imposing a series of concussive blows on the same impacted area of concrete in one tamping stroke.

12. In a concrete tamping machine, :1

- frame, a mold thereon, a cross head slidable in said frame, a weight subjacent and close to the bottom of said cross head, a tamper body subjacent said weight and having a weight impact shoulder in spaced relation below Y said weight, said body having a shank in lost with the concrete and thereby take up the. lost motion between said-cross head and tamper and cause the former to strike the latter and said Weight subsequently engag.

ing said shoulder, thereby insuring a triple I tamping impact in one tamping stroke.

In witness whereof I hereunto aflix my signature.

EDWARD J. soHUH. 

